Walter b



(No ModeLf W. E. TAFT.

MACHINE FOR MAKING DRILL BLANKS.

No. 318,322. Patented May 19, 1885.-

INVIN T H: MM 5% N. PETERS PhnRo-Uth v UNITED STATES PATENT OFFICE.

\VALTER E. TAFT, OF PROVIDENCE, RHODE ISLAND, ASSIGNOR, BY DIRECT AND MESNE ASSIGNMENTS, TO THE TAFT TVIST-DRILL AND TOOL COM.

PANY, OF SAME PLACE.

MACHINE FOR MAKING DRlLL-BLANKS.

*PECIFEGATION forming part of Letters Patent No. 318,322, dated May 19, 1885.

Application filed March 3, 1884. (No model.)

To all whom it may concern:

Be it known that I, WALTER E. TAFT, of the city and county of Providence, and State of Rhode Island, have invented certain new and useful Improvements in Machines for Making Blanks for Twist-Drills, Gimlets, &c., of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming a part ofthis specification.

My invention relates to machines for forming the straight grooves in the blanks for drills, 850.; and the object of my invention is to improve the construction of such machines and to increase the efficiency of their operation.

My invention consists in the peculiar and novel construction and arrangement of certain parts of the machine, as hereinafter described and claimed.

In order that my invcntion'may be fully understood, I will proceed to describe it with reference to the accompanying drawings, in which Figure 1 is a side elevation of a portion of the machine-frame with my improvements applied, the latterbeing shown partly in section. Fig. 2 is a plan view of the same. Fig. 3 is an end elevation of the groove-formingrolls detached from their bearings, but in relative operative position. Fig. 4 is a side elevation of the grooved drill-blank, an end View of the same being shown just below the side view.

The tools which the machine embodying my invention is designed to make are made from a blank which is provided with two straight longitudinal grooves arranged oppositely and of decreasing depth from the cutting-point to the terminus. The grooved blanks are subsequently placed in a twisting-machine, by which the straight grooves are transformed by twisting the blank into spiral grooves.

As before stated, my invention relates to machines for forming the straight grooves in the blank.

In the said drawings, A designates the bedl'rame of the machine, which may be of the usual or any preferred form suitable to the purposes of drill-blank-grooving machines.

Upon one end of the frame are mounted two vertical frame-pieces, 13, between which are mounted two rolls, 0 G, the ends of the roll 0 being journaled fixedly in the frames,while the ends of the roll 0 are journaled in blocks arrangedto move vertically in the said frames.

D designates a screw, which extends downwardly into the frame and works in a screw socket or nut thereon, and the lower end of which screw is secured to the movable block of the roll 0.

d designates a hand-wheel for the screw D, there being one such screw and wheel for each frame and two for the roll 0, and the purpose of said screws being to adjust the roll C vertically.

The rolls 0 C are each provided witha segmental fiange, c 0, respectively, which is of greater radius at the points 1 2, and gradually decreases in radius to the points 3 4. The flanges c c are each rigidly secured to the roll,

and are held against endwise movement on x the rolls by sleeves 0* 6 which are slipped endwise upon the rolls, and also secured from turning thereon by collars c, which are each screwed upon one end of the roll, the flange being confined between an enlarged portion of the roll and the end of the sleeve.

E designates a shelf or rest, which is supported between the frames B, and which is formed with a central aperture to receive the flange of the roll 0.

Upon the shell E are placed two sliding guideblocks, F, each of which carries one or more friction disks or rollers, f, upon its inner side, and is held in working position by adjusting-screws f, attached at one end to the slide, and passing thence outwardly through the frames B, the purpose of such screws being to 1110K8 said slides toward and away from each other, as desired.

G designates the former, which is made in two equal parts, the line of contact between the two parts passing longitudinally through the device midway of its length. The two parts of the block touch only at their ends, as shown in Fig. 2, so as to leave along opening in the upper and lower sides of the former for the reception of the roller flanges or dies 0 c. The interior of each member of thefornier is provided with a lateral elongated recessto form the sides of the drill, as shown in Fig. 1..

- which the blank is twisted so as to turn the The operation of the device is as follows: The slides F are drawn aside by their screws f and the rolls are set with the deepest ends of their flanges contiguous to each other. The former is then opened and a blank placed within it. The closed former is then placed upon the shelf E with its opening directly over the aperture of the shelf, and the slides are forced together so as to bind the former between them. Aftcr the upper roll, 0, has been lowered upon the blank the machine is started, and as the rolls revolve the flanges c 0 form the grooves h h in the blank H, the said grooves being of greater depth at the cutting-point of the drill than at their opposite ends, owing to the decreasing thickness of the flanges. As the rolls 0 G revolve, the block G moves between the disks f, and the spreading of the blank within the former fills the latcral recesses of the same, thus forming the proper shape of the sides of the drill. The arrangement may be such that the blank will be forced out of the block by the rolls while the block remains stationary. After these operations have been completed the grooved blank is removed from the machine and subjected to the action of a twisting-machine, by

grooves into spiral lines.

Having thus described my invention, I claim 1. In a machine for grooving drill or tool -1 blanks, the combination, with a pair of rolls having each a flange of unequal radius, of a former constructed to hold the blank and form the sides of the tool, and also to receive the roll-flanges for forming the grooves, substan tially as described.

2. The combination, with a former and a pair of rolls having flanges of decreasing depth, of a pair of sliding blocks arranged to hold the former and to allow it to move during the operation of grooving, substantially as described.

3. The combination, with the frames 13 B, the screws D, and the adjustable roll 0, having the flange c, of the fixed roll 0, having the flange c, the shelf E, having the central aperture, the guide-blocks F, having disks f, r

and the screws f, all constructed and arranged substantially as described.

4. The combination, with the frames B B, carrying the shelf E, and the operating-screws D, of the rolls 0 O, carrying the flanges c c, the sleeves 0 the slides F, with their adj 11sting-screws and disks f, and the former G, all constructed and arranged substantially as and for the purposes specified.

In witness whereof I have hereunto set my hand.

\VALTER E. TAFT.

Witnesses:

J. A. MILLER, J12, M. F. BLIGH. 

